Speed of pysnmp

[Ilya Etingof]

Roy Smith <roy at panix.com> wrote:

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> It's entirely expected that the pysnmp version had much higher CPU times 
> (from about 0.25 to 1.5 total user+sys).  What I don't understand is why 
> the real time went up so much, from about 4 seconds to about 9 seconds.  
> Most of the time doing a mib walk is waiting for UDP packets on the wire.

My guess is that Python code takes up so much CPU time on a single SNMP message
processing, that OS's likely to schedule out (involuntarily context switch) python
process for greater number of times than it is with C version.

In other words, if you burn 0.01 CPU sec, you're likely to get it done within a
process's time slice. Although, when you burn 10 CPU secs in bulk, you're likely 
to 1) run out of process's time slice (context switch) 2) compete for CPU time
with other processes on the system. In the end, both factors might contribute 
to real time increase...

-ilya